Extendable boom remote control system



Aug..18, 1970 s. l.. BOOMGAARDEN ETAL 3,524,521

EXTENDABLE BOOM REMOTE CONTROL SYSTEM s. L. BOOMGAARDEN ETAL 3,524,152EXTENDABLE BOM REMOTE CONTROL SYSTEM I A Aug. 18, 1970 5 Sheets-Sheet 2Filed Jan. 8, 1969 INVENTORS SE1/.EM L. 5004164451254),

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EXTENDABLE BOOM REMOTE .CONTROL SYSTEM Filed Jan. e, 1969 y 3SheeS-Sheet PIES - INVENTORS Sra/5m L. .Boo/146442195, 02.40 c/ dof/#50MUnited States Patent O 3,524,521 EXTENDABLE BOOM REMOTE CONTROL SYSTEMSteven L. Boomgaarden, Richfield, and Orlo J. Johnson,

Lakeville, Minn., assignors to Tel-E-Lect, Inc., Minneapolis, Minn.

Filed Jan. 8, 1969, Ser. No. 789,849 Int. Cl. B66f 11/04 U.S. Cl. 182-469 Claims ABSTRACT F THE DISCLOSURE A remote control system for anextendable boom assembly in which the control system includes operatinghandles connected through a cable system to stationary valve controls onthe stationary portion of the boom. The cable system is connected overmovable control frame parts which change the position of the supportingsheaves to compensate for slack in the cable with boom extension andcontraction.

Our invention relates to extenable boom assembly control apparatus andmore particularly to an improved control system for extendable boomswhich compensates for slack in the cable system of the same.

Extendable boom systems employed in aerial towers have the problem ofcompensating for the control system length with boom extension andcontraction. The present systems of this type in use employ complicatedcontrol mechanisms and special power actuators to perform thiscompensation. Further, where such systems employ insulated boomextensions and Work baskets, the problem of insulating the controlsystem for the same requires a complicated structure to permitinsulation of the control system from the stationary portion of thecontrols. In the present invention, a simplified control apparatus isprovided which adjustably positions the cable system to compensate forthe change in cable length with boom extension and contraction andincludes the use o f insulating rods in the cable system to insulate thework platform on the end of an insulated boom for safety of personneltherein. The improved control apparatus employs a carriage mounting onat least part of the pulley system for the control cables which isadjustably positioned in accordance with boom extension Without therequirement of separate actuators and in proportion to the boomextension such that cable length will be automatically compensated forto maintain uniform tension on the same. The location of the controlsystem and the arrangement of parts permits the introduction ofinsulating sections in the control cable system to insure electricinsulation between the control handle and the control actuators on thestationary portion of the boom.

It is, therefore, the principal object of this invention to provide animproved control apparatus for an extendable boom.

Another object of this invention is to provide in a control system foran extendable boom a simplied arrangement for adjusting for cableextension and contractlon.

Another object of this invention is to provide in a control apparatus ofthis type a simplified arrangement for maintaining electrical insulationin the control portion of the same.

These and other objects of this invention will become apparent from areading of the attached description, vtogether with the drawingswherein:

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FIGS. 1 and la are a continuous side elevation view of the improvedcontrol apparatus for an extendable boom with parts in section;

FIGS. 2 and 2a are a continuous plan view of the control apparatus ofFIG. 1; and

FIG. 3 is a schematic view of the improved control apparatus showing thearrangement of parts.

Our improved remote control apparatus for an extendable boom is shown inthe drawings with the boom itself, indicated in phantom in FIGS. l andla, and schematically in FIG. 3. The details of the boom are omittedsince they lmay take varying forms, but it will be understood that anextendable boom will normally include a main or outer portion 10 withone or more inner extendable portions or boom members 11 and 12. Such aboom will normally form a part of the mobile aerial tower or equivalentstructure in which the main boom element is mounted on some type ofsupport, such as a rolling support, and is pivoted about one or moreaxes, normally two axes, through a structure (not shown). A boomassembly of this type will normally include a number of separateactuators for the purpose of extending the boom members or elements 11and 12 relative to one another and to the main stationary boom portionto provide a generally elongated structure for a working purpose. Inmany instances, such a boom configuration will carry a personnel basket(not shown) at the end of the same to provide a mobile aerial platformor tower and, in such instances, the structure of one or more of theboom elements, normally the end or stinger boom member 12, will be madeof a di-electric material as well as the personnel carrying basket toelectrically insulate the end of the boom from the metallic boomstructure, that is the remaining boom members, as well as the supportingstructure and wheel support.

v In the present invention, control apparatus for such a boom assemblyis provided which will locate manually operating handles or levers,indicated generally at 30, in the vicinity of the end of the boomstinger or adjacent the boom stinger or inner boom element 12 adjacentthe personnel carrying basket attached thereto, which control handleswill operate mechanically the controllers located on the main boomelement 10 adjacent the base of the same, the controllers beingindicated generally at 35. These controllers, which are shown herein ashydraulic valves, would be coupled to and control hydraulic actuators(not shown) positioned on the main boom assembly and its supportingstructure (not shown) for the purpose of moving the entire boom assemblyabout the two axes of movement and for extending and retracting the boomelements or boom assembly. This controller or valve assemblyincorporates three separate valves, indicated at 38, 39 and 40, whichare mounted in a single valve housing and include a plurality of outletports 41, 42, and 43, with appropriate inlet ports, indicated at 45, forthe purpose of providing bi-directional control to the hydraulicactuators associated with the boom assembly and aerial connectionsextend between the inlet and outlet ports 41-45, hydraulic source linesand associated hydraulic actuators (not shown) for the boom assembly forthe hydraulic control circuit.

The frame member 55 of the control apparatus is basically an elongatedstructure upon which the Valve assembly 35 is mounted through suitablemeans such as bolts, indicated at 60. Also positioned on the framemember 55 is an elongated channel member 65 which is supported thereonthrough suitable brackets 66, the channel member being generallyrectangular in cross section and tubular with a slot, such as isindicated in FIG. 2 at 618, extending along the extent of the same. Thetubular track structure 65 supports a carriage member 70 which is alsogenerally rectangular in cross section and elongated in form. Thecarriage member mounts a bracket 72 with an upwardly extending flange 73upon which is positioned a pair of roller members 76 with the upwardlyextending flange portion 73 extending through the slot 68 in thecarriage member and with the rollers 76 positioned within the tubularmounting bracket for guiding the rollers along the extent of the same.The carriage member is generally rectangular in cross section and isspaced from the surface of the plate-like frame 55 through its mountingon the tubular guide or frame 65 so as to be guided along the extent ofthe mounting frame 55 through support of the flange 72 with the rollers76 thereon. The ange 72 is located near one extremity of the carriagemember 70 to hang or suspend the carriage member at this extremity onthe frame 55. The opposite extremity of the carriage member is supportedby an upwardly extending flange '80 with a roller 82 thereon which bearsagainst the undersurface of the carriage member and near the lowerextremity of the mounting plate beneath the end of the tubular carriage70. It will be noted in the dra-wings that the carriage member 70extends beyond the extent of the same' and in turn mounts a tubularmember 90 which is slidably positioned in the carriage member 70 andadapted to move relative thereto. The inner tubular member 90 is made ofan insulating or di-electric material while the carriage member 70 is ofa metallic material.

The carriage member 70 is adapted to move relative to the frame member55 ou its roller supports through connection with the tubular member 90and a cable system, to be hereinafter described, associated therewith.Thus, as will be seen in FIGS. l and 2, and schematically in FIG. 3, themounting frame 55 includes a plate 100 with a cable 102 attached at itsextremities to the same, the cable being directed over a roller memberor pulley 5 mounted on a ange 106 on one end of the carriage member 70and a second pulley or sheave 107 mounted on a ange 10'8 and positionednear the other end of the carriage member 70. The cable 102 is loopedacross each of the pulleys such that the upper portion of the loopextends outside of the carriage member 70 while the underside isdirected into the interior of the carriage member through suitable slots111 therein and at the midpoint opposite the connection with the tlange100 is connected to the end of the tubular member 90 through a suitableconnecting bracket 110. Thus, as the tubular member 90 moves within thecarriage member 70, the cable will move over the rollers 107, 105 andcause the carriage member 70 to be moved with the tubular memberrelative to the mounting frame 55 and on its supporting track 65 androller member '82. The tubular member 90 will be withdrawn from thecarriage member as the tubular member is withdrawn since the cable 102,as it rolls over the sheaves or pulleys 105, 107, will pull the carriagemember along with the same with the tubular member 90 moving out of thecontines of the carriage member a distance slightly less than one-halfthe length of the cable 102 as the carriage member 70 moves relative tothe mounting plate 55 the same distance. The purpose of this mounting isto maintain tension in the mechanical cable system, to be hereinafterdefined, extending between the operation handles 30 and the linkagesassociated with the valve stems or actuators of the valve assembly 35for operation ofthe same.

As will be seen in FIGS. la and 2a and schematically in FIG. 3, thetubular member mounts a hollow connecting sleeve which is secured to theend of the tubular member and is made of a metallic or rigid material.This structure in turn mounts a hand linkage support comprised of aplurality of handles 121, 122 and 123 pivotally mounted in the handleframe 120 and carrying transversely extending linkage tie members 125 atthe end of the same. In addition, the hollow support frame mounts aplurality of stacked pulleys or sheaves, indicated generally at and 133,over which the cable extends. The ends of the cable tie link 125 mountthe ends of the plurality of cables, indicated generally at 140, whichextends over the pulleys 130, 133 and connect to cable rods located inthe tubular member 90. The rods 150' are made of a di-electric materialand serve as a splice or section of the cable within the insulatingsection of the control apparatus to provide insulation in the manualcontrol linkage between the handles and the valves. The opposite ends ofthe rods 150 connect to extensions of the cables 152, 153 which extendthrough the carriage member 70 and over pairs of pulleys 162, 16'3mounted on suitable support frame member 164 in the end of the carriagemember with the cables being fed back along the extent of the frame andover similar stacked guide pulleys 172, 173 on the lower portion of thesupport frame 55 with the cables extending back along the extent of thesupport frame to a inal set of pulley member 175 mounted on a suitablebracket 176 and located on the opposite end of the mounting frame forthe control apparatus. Adjacent the final sets of pulleys 175, the cablesystem connects to a lever assembly 180 formed of pivoted lever members172, 183- and 184 which are mounted on the support frame throughsuitable supporting brackets, indicated generally at 190. rIhe free endsof these levers connect to operating levers 192, 193 and 194 for thevalves 38, 39 and 40, respectively, and are connected to the valve stems50 of the same to move the valve stems longitudinally and in areciprocating manner to operate the valve in a controlling function.

As will be seen in the plan view, an individual cable is connectedbetween each of the respective handles and one of the linkage systemsand each set of pulleys in stacked relationship contains a separatepulley member or sheave for each cable connecting the handle with therespective valve. The cable extremities secured to the cable linkagemembers 125 on the handles extend over pairs of pulleys 162, 163 on thecarriage member and on the end of the mounting frame 52, as at 172, 173,to separate and guide the sides of the cable loop extending between thehandle and the final pulley set 175 with the linkage members beingconnected intermediate the extent of the cable system. Thus, theindividual handles 121, 122 and 123 with their respective cable systems,which are normally made of a metallic material, each include theinsulating rods 150 within the tubular portion or member 90 of thecontrol assembly mounting the handle frame 120 so that the handles areelectrically insulated from the valve assembly and insulation ismaintained between the eX- tremities of the control apparatus.

In the mounting of the control assembly on the boom elements, themounting plate 55, as previously described, 1s attached to the mainIboom element or outer boom member 10. The inner boom element or thestinger port1on of the expandable boom, which is normally made of adi-electric material such as -tiber glass, has attached thereto thecontrol handle portion of the control assembly which includes thedi-electric tube 90 which is similarly made of -ber glass together withthe handle mounting frame 120 secured thereto. Thus, as is shown in FIG.1b, the boom element 12 will normally include a mounting bracket 200 towhich is selectively attached by means of a pin a connecting Iliange 201on the handle mounting frame 120. Similarly, the intermediate or secondboom element 11, where it is used, will include thereon a roller supportmember, such as is indicated at 210, which is adapted to receive andsupport the tubular member 90 as it is extended. For transportationpurposes to keep the cables on their respective pulleys, the tubularmember will normally include a separate catch or latch flange 215through which a pin is adapted to be inserted, such as is indicated at216, to engage a flange 218 connected to the carriage member 70. Thiswill prevent the tubular member from sliding out of the contines of thecarriage member during transportation and will insure that the cablesystem for the individual cables connected to the handles 121 123 willbe kept in position on their respective pulley members or guides duringtransportation. Such a pin is removed when the apparatus is ready forusage and the structure, that is the inner boom member 90, is extendedand engaged with the stinger or inner Iboom element 12 by means of thelatch members 200, 201.to be fxedly connected thereto for operation withthe boom elements. The personnel carrying -basket (not shown) willnormally be positioned adjacent this location so that an operator mayoperate the handles to move the valve `members and control theassociated motors of the boom assembly in the operation, that is themovement and extension. and retraction of the boom. s

In operation, each of the handles of the control assembly may beindependently operated to selectively operate one of the valves of thevalve assembly 35 on the control frame through the cable systeminterconnecting the two. As the boom is extended or retracted, the cablewill be kept taut to insure proper valve operation by fmovement of thecarriage 70 and inner tubular members 90. As the tubular member moves,its connection with the cable 102 will cause the carriage member 70 tomove or lbe pulled along through cooperation with the rollers 105, 107at the ends of the same. The carriage member and tubular members willmove with the boom extension or retraction to maintain the cables tautand operative such that they are actually moved only through operationof the control handles. The inserted insulating rods 150, forming a partof the cables within the tubular member, insures that di-electricinsulation is maintained between the control handle section 30 and valveassembly 35 of the control apparatus to be consistent with and completethe electrical insulation of the control basket from the ground orremaining portion of the supporting boom structure and the boom itself.This improved control apparatus requires no separate motors, andmovement of the carriage system is controlled fby |boom movement whichwill displace the supporting rollers, that is one of the supportingrollers or sheaves for the connecting cables between the handles and thevalves so that proper length of cable will be maintained at all times toinsure that no slack will appear therein.

What is claimed is:

1. Control apparatus for extendable boom assembly having a main boommember with at least one telescopic inner boom member and with a workplatform at the end of the outer most inner boom member including motivemeans operative to retract and extend inner boom members relative to themain boom member comprising, a base frame adapted to be attached to 'themain boom member, control means adapted to be connected to and controlthe operation of the motive means of the extendable boom assembly tocause retraction and extension of the inner boom members, said controlmeans being mounted on the base frame, a carriage member slidablymounted on the base frame, a hollow tubular member slidably mounted inthe carriage member and having an outer extremity projecting therefrom,said tubular member being adapted to be connected to the outer most endof the inner boom member adjacent the work platform, control handlemeans mounted at the end of the tubular member and adapted to be locatedadjacent the work platform to be operated from the work basket, acontrol cable system connecting respectively the control handle with thecontrol means on the base frame Afor operation of the same, said cablesystem being guided by sheaves on the carriage member and on the baseframe, and an additional cable system having a pair of guiding sheavespositioned at the ends of the carriage member with the cable systembeing connected to the base frame and the tubular member at, oppositelpoints thereon to cause the carriage member to slide with movement ofthe tubular member to compensate for slack in the control cable systemwith relative movement of the boom members.

2. The control apparatus of claim 1 in which the control means on thebase frame include a plurality of controllers some of which are adaptedto control articulation of the boom assembly and in which the controlhandle means includes a plurality of control handles each with aseparate cable system guided over separate sheaves on the carriagemember and the base frame to operate respectively the plurality @fcontrol members.

3. The control apparatus of claim 1 and including track means positionedon the base frame and roller means mounted on the carriage member forslidably mounting the carriage member on the base frame.

4. The control apparatus of claim 3 in which the control cable systemconnecting the control handle with the control means on lthe base frameextends through the tubular member and the carriage member.

5. The control apparatus of claim 4 in which the tubular member is madeof an insulating material and including insulating rod means positionedin the control cable system within the tubular member to insulate thecontrol handle from the control means.

6. The control apparatus of claim 4 and including additional guideroller means positioned relative to the carriage member opposite thetrack and roller guiding the same to guide the underside of the rollerwith said additional guide means` being positioned on the base frame.

7. The control apparatus of claim 1 in which the additional cable systemconnected to the carriage member includes roller means positioned oneither end of the carriage member and a slot in the carriage memberthrough which a portion of the additional cable system extends with thecable system being connected to the tubular member within the carriagemember and to the base frame outside of the carriage member.

8. Control apparatus for extendable boom assembly having a main boommember with at least one telescopic inner boom member and with a workplatform at the end of the outer most inner boom member including motivemeans operative to retract and extend inner boom members relative to themain boom member comprising, a base frame adapted to be attached to themain boom member, control means adapted to be connected to and controlthe operation of the motive means of the extendable boom assembly tocause retraction and extension of the inner boom members, said controlmeans being mounted on the base frame, a carriage member slidablymounted on the base frame, a hollow tubular member slidably mounted inthe carriage member and having an outer extremity projecting therefrom,said tubular member being adapted to be connected to the outer most endof the inner boom member adjacent a work platform, control handle meansmounted at the end of the tubular member adjacent the work platform tobe operated from the work platform, a control cable system connectingrespectively the control handle with the control means on the base framefor operation of the same, said cable system being guided by sheaves onthe carriage member and on the base frame, and compensating means forthe control cable system to compensate for the change in distancebetween the control handle and the control member with extension andAcontraction of the boom assem- 7 bly including additional cable meanscoupling the tubular member with the carriage member to cause thecarriage member to slide on the base frame and change the position ofthe sheaves thereon relative to the base frame with movement of thetubular member.

9. The control apparatus of claim 6 and including a further roller guidemeans adapted to be positioned on an inner boom member to engage thetubular member support the same.

8 References Cited UNITED STATES PATENTS 1/ 1967 Verrell et al. 182-2U.S. Cl. X.R.

uNrllm H'IA'rlcs IA'llcN'r nwlmc (IER'IIFICA'IE 0l" CORRECTION Patent;No. 3:524:521 DatefLAugust 18. 1970 nventor(s)oom zaarden, Steven L. zand Johnson. Orlo J.

It is certified that error appears in the above-identified patent andthat said Letters Patent are hereby corrected as shown below:

Page 7, Line 8, after "tubular member", insert the following and.

NOV. 17,1970

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